Many vehicles carry cargo from place to place. Trucks, trains, airplanes, cars, boats, and other vehicles often have storage compartments or beds that can be used to transport cargo.
Sometimes the cargo must be stored in an area of the storage compartment that is difficult to reach. For example, if the cargo is heavy it may be required to be placed in a certain portion of the storage compartment or bed so that the payload is properly distributed. As another example, if there is a large amount of cargo, at least some of the cargo might be placed in an out-of-reach area of the storage compartment so that the rest of the cargo can fit. And also, the cargo can shift into an out-of-reach area during transport. For example, if a pickup truck brakes quickly, cargo in the truck bed may slide toward the front of the truck where it is difficult to reach.